I. Addition, subtraction, multiplication and division of numbers
Addition and subtraction within 1 and addition and subtraction within 10 are the most basic knowledge points in junior high school mathematics. Students need to master the addition and subtraction of each number and be able to use it flexibly.
Addition and subtraction within 2.20, addition and subtraction within 20 Based on addition and subtraction within 10, this paper introduces the calculation methods of carry and borrow, and requires students to master all kinds of principles and methods of carry and borrow.
3, multiplication formula, multiplication formula is the content that junior high school mathematics must master, it can help students to multiply quickly and improve their mathematical operation ability.
4. A preliminary understanding of division. The preliminary understanding of division is one of the key points of mathematics learning in grade two. Students need to understand the meaning and basic nature of division, and be able to perform simple division calculation.
Second, time addition, subtraction, multiplication and division
1, 24-hour system, which is the basis of time system, requires students to master the expression method of 24-hour system and the conversion of time units.
2. The addition, subtraction, multiplication and division of hours, minutes and seconds and the addition, subtraction, multiplication and division of hours, minutes and seconds are one of the most basic calculation methods in the time system, and students are required to master the calculation methods of addition, subtraction, multiplication and division of each time unit skillfully.
Third, the length of addition, subtraction, multiplication and division
1, length unit conversion, length unit conversion is one of the more important knowledge points in junior high school mathematics, which requires students to master the conversion methods and usage scenarios between different length units.
2. Addition, subtraction, multiplication and division of meters, decimeters and centimeters. Meter, decimeter and centimeter are the most basic units in length measurement, so students need to master the calculation methods of addition, subtraction, multiplication and division of each unit skillfully.
Fourth, other formulas
1, area formula, rectangular area = length x width; Square area = side length × side length; Circular area =πx radius? ; The above are some basic area formulas, and students need to master their calculation methods and usage scenarios.
2. Volume formula, cuboid volume = length× width× height; Cubic volume = side length × side length × side length; Cylinder volume =πx radius? X height; Cone volume =πx radius? X height/3; These are basic volume formulas, and students need to master their calculation methods and usage scenarios.
3. Surface area formula: cuboid surface area =2x length x width +2x length x height +2x width x height; Cubic surface area =6x side length? ; Cylinder surface area =2xπx radius x height +2xπx radius? ; These are basic surface area formulas, and students need to master their calculation methods and usage scenarios.